Welcome to Building Character, TDF Stages' ongoing series about actors and how they create their roles

You can soak up the transgressive, expertly choreographed chaos of Clybourne Park, now on Broadway at the Walter Kerr, without noticing its nods to a certain classic of 20th-century theatre. But if you miss the references, don't worry. You're in good company.

"I probably shouldn't admit this," says Jeremy Shamos, "but when I did the initial reading of this play, I didn't realize it was based on A Raisin in the Sun."

More than any other member of the seven-member cast, Shamos, who just received a Tony Award nomination for his performance, might be expected to have the CliffsNotes to Lorraine Hansberry's canonical 1959 drama. Bruce Norris's Pulitzer Prize-winning play uses Raisin as a springboard to depict five decades' worth of racial misunderstanding and mistrust in a middle-class neighborhood of Chicago. And Karl Lindner, the milquetoast bigot that Shamos plays in the first act of Clybourne, is the only direct carryover from Hansberry's script.

All the same, Shamos insists that Raisin was a tangential force in rehearsals. "We approached this like what it is, which is a new play," he says, "and the fact that my character crosses over just means I had a few more details about his circumstances." In fact, Shamos steered clear of the movie version of Raisin at Norris's insistence.

Both acts of Clybourne take place at 406 Clybourne Street, the home that the African-American Younger family is about to move into in Raisin. Act I explores this event from the perspective of the white family that is moving out, despite Karl's increasingly desperate pleas. As the representative of the neighborhood's "Improvement Association," he's worried what integration will do to his community.

Act II flashes forward 50 years, and the racial demographic of the neighborhood has once again been upended. This time Shamos plays one half of a white couple looking to gentrify an area that, over the intervening decades, has become almost entirely African-American.

This lurch in time is hardly the only one that Norris and director Pam MacKinnon have created. "More than a lot of shows, we make a lot of internal veers and swerves," Shamos says. "What Bruce does really beautifully is create a world where you're really glad somebody's speaking up. You think, 'They're saying what I might say if I had the courage.' And then he has them take it a little too far and say too much. I think this play makes people feel really uncomfortable but also weirdly liberated."

Shamos and about half of the cast have been with Clybourne since its first reading. All seven actors were part of the 2010 Off-Broadway premiere at Playwrights Horizons and the recent Los Angeles run, which came right before the move to Broadway. "People wanted to move it to Broadway right after Playwrights," Shamos says, "but it had no stars and no British people."

(The L.A. run was at the Mark Taper Forum, which simultaneously ran a production of A Raisin in the Sun.Shamos says audience members who had seen Raisin the night before were all too happy to fill him in about any discrepancies between the two Karl Lindners.)

That relatively long break between performances proved extremely beneficial to the actors. Shamos says, "Rehearsals at the Taper were a real luxury because we already knew the play. It sort of grew under the soil during those two years, and it's healthier as a result."

Shamos, 42, is no stranger to switching personae mid-show. Among his many New York credits are costume-swapping parts in The Complete Works of Shakespeare (Abridged), Miss Witherspoon, and Gutenberg! The Musical!

While he has no set procedure for taking on multiple roles---"So much of that depends on the writing"---he does say that Norris, MacKinnon, and the cast approached the two acts of Clybourne Park as two different plays.

New York and Los Angeles audiences have differed a bit in their response to Karl, he adds: "People in L.A. really wanted to condemn Karl, to the point where they didn't even listen" to comparably racist material from the other characters. But both coasts have had the same reaction when the escalating anger finally erupts.

"As a rule, I would say that the last half of the second act is pretty much like a rock concert. Particularly on Broadway, people are really excited to see the niceties cast aside and the gloves come off."

Eric Grode is the author of the recently released "Hair: The Story of the Show That Defined a Generation" (Running Press)